Separation of oxygenated organic compounds



Jan. 5, 1954 W. E. HANFORD SEPARATION OF' OXYGEINATED ORGANIC COMPOUNDSFiled NOV. 30, 1948 REAcTloN SYNTHESIS RECTOR PRODUCT CONOENSER A T FEED7 7 IO l2 I3 I4 GAS cs2 REcYcL: REcYcLE E |5 o 37 l; C52 KoH E 0|L 2O l.2|

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HYDRocARBoNS 46 44 S, 45 m (DE 5; 'f g; JNVENToR. y go ,Z8 WILLIAM E.HANFORD P" U BY .J j" E @J1-M 4 z3 WJWW ATTORNEYS Patented Jan. 5, 1954SEPARATION OF OXYGENATED ORGANIC COMPOUNDS William E. Hanford, ShortHills, N. J., assignor to The M. W. Kellogg Company, Jersey City, N. J.,a corporation of Delaware Application November 30, 1948, Serial N o.62,621 20 Claims. (Cl. 26o-450) This invention relates to the separationof oxygenated organic compounds. In one aspect, the invention relates tothe separation of alcohols from the reaction effluent produced in thehydrogenation of oxides of carbon. More particularly, in this aspect theinvention relates to the separation of alcohols present in an oilcondensate product obtained from the condensation of the reactioneflluent produced in the hydrogenation of oxides of carbon.

It is known, that hydrogen and oxides of carbon, particularly carbonmonoxide, may be made to react exotherrnically in the presence ofcertain catalysts and under specific reaction conditions to formhydrocarbons and alcohols having more than one carbon atom per molecule,and other oxygenated organic compounds which may comprise aldehydes,ketones, acids and esters. In general, the synthesis of hydrocarbons andoxygenated organic comp-ounds by the hydrogenation of carbon monoxide,is accomplished in the presence of a metal or an oxide of a metal, suchas one chosen from group VIII of the periodic table, as a catalyst atpressures below about 500 pounds per square inch gage and attemperatures below about 750 F.

Various methods have been practiced to eiect the reaction of hydrogenand carbon monoxide to produce organic compounds. Among these methodsare those known as fixed-bed catalyst operations and huid-bed catalystoperations. 'Ihe xed-bed operation comprises passing a reaction mixtureof hydrogen and carbon monoxide through a stationary bed of catalyst ina reaction zone; and the fluid-bed operation comprises passing such areaction mixture through a iinely divided catalyst mass, suspended inthe reaction mixture in the reaction zone, under conditions such that aso-called pseudo-liquid dense phase of solids is formed.characteristically, certain reaction conditions are necessary for eachof these processes and for the particular catalyst used. The synthesisfeed gas or reaction mixture comprises a mixture of about 1:5 mols ofhydrogen per mol of carbon monoxide and may be prepared by various meansincluding the catalytic conversion of natural gas, steam and carbondioxide. It will be understood, however, that While the hydrogenation ofcarbon monoxide has been referred to specifically, such above-referredhydrogenation is of wider application and includes within its scope thehydrogenation of any suitable carbon oxide.

The reaction eiiluent thus produced in the aforementioned hydrogenationof an oxide of carbon,

comprising hydrocarbons, alcohols and other oxygenated organic compoundswhich may include aldehydes, ketones, acids and esters, is obtained inthe Vapor state in the form of reactor outlet gases. These gases aregenerally passed through one or more condensation zones in which theyare cooled to temperatures within the range between about 40 F. andabout 150 F. The resulting condensate then separates into an oilcondensate product, a Water condensate product and an uncondensed gasproduct, each product containing the aforementioned oxygenatedcompounds.

It is, therefore, an object of this invention to provide an improvedprocess for the separation of alcohols present in the oil condensateproduct obtained from the condensation of the reaction eflluent producedin the hydrogenation of oxides of carbon.

Another object of the invention is to provide an improved process forthe separation of alcohols from other oxygenated organic compounds andhydrocarbons present in the oil condensate product obtained from thecondensation of the reaction eiiluent produced in the hydrogenation ofoxides of carbon, economically and efciently.

Other objects and advantages inherent in the invention will be apparentfrom the following more detailed disclosure.

In accordance with the general process of the invention, as more fullyhereinafter described, it has been found that the aforementioned oilcondensate product may be treated with carbon disulde and an alkali toconvert alcohols present to their corresponding xanthates. Thesexanthates are next separated from hydrocarbons and other oxygenatedorganic compounds present in the resulting mixture, by treating thismixture with a solvent having a preferential solvent power for thexanthates. The extract thus produced is next contacted with a mineralacid to regenerate the alcohols from the xanthates contained therein,and the alcohols thus produced are subsequently separated from theformed alkali salts and reformed carbon disulfide.

In another modification of the general process of the invention, as morefully hereinafter described, the aforementioned oil condensate productis rst contacted with a solvent for the alcohols and other oxygenatedorganic compounds contained therein, in order to eiect their separationfrom hydrocarbons present. The extract thus produced, comprisingalcohols and other oxygenated organic compounds, is next treated WithCarbon disulfide and an alkali to convert the ment of the process of theinvention. While the-L10.`

invention will be described in.detail, .by reference. to the embodimentillustrated in the drawing, it should be noted that it is not intendedthat`itv be limited thereto, but is capablezfotiotherlem--- bodimentswhich may extendbeyond'thefscopeof the apparatus illustrated.Furthermore, the-distribution and circulation ofzliquidssandvaporsv isillustrated in the drawing by a diagrammatic representation of theapparatus employed. Valves, pumps, compressors and other mechanicalelements: necessary to effectA the transfer:v of: liquids and' vaporsand'to' maintain"theconditionse of temperaturev and pressureA necessaryto carry,l out the function of thev apparatus, areiomitted morder tosimplify thedescription.v It` will'be'V understood, however,- thatmuchequipment` of', this nature is necessary andwill besuppliedby. thoseskilled inzthe art.

Referring; to the. drawing. a synthesis feed. comprising a.reactionmixture of hydrogerrand` an oxide of carbon, such as carbonmonoxide; at; varying mol ratios, such asl 2:1, is supplied. throughline I and transferred through this-line tol a synthesisreactionvessel,represented in the drawing by reactor III, In reactor I I- the reaction:mixture is contacted witha hydrogenationicata-` lyst, such. asarreducedk ironY or. cobalt catalyst, at temperaturesvaryingr betweenabout 300 F. and about 700 F. and at pressures vary-ing' be-` tweenabout atmospheric'pressureand about 500 pounds per square inch, and isfcarried outaccordingV to the aforementioned conventional iixed-bedorfluid-bed. operations. The resulting` reaction product obtained* from'reactor II is withdrawn through line- I2; productv is in the vapor formsubstantiallyv as=it comes from the reactor within thezaforementionedtemperature range, containing water, methane and higher hydrocarbons,-and. oxygenated. organic compounds comprising methanol and higheralcoholsy` andmay., also comprise. C2"V and higher. acids, andalsoaldehydes, ketonesfandt estersdepending upon the condition of .the:reac-l tion This product is. rst: cooledto condense substantially largequa-ntitiesofM normally liquid. components. Conveniently,condensationmaybe obtainedY in. a plurality. of. cooling stages.4whichare represented. diagrammatically4 inthe draw-- ing by condenser..I 3 with :which line.. I2.. connects: From condenser I 3. the resultingAmixture of .con-- densate anduncondensed, gases.. passes through line I4to aV separator. I5. InftheJz-itter,` theuncondensed gases are-Withdrawn through; line I 6: andrecycled', via thisline, into reactor. II.through line I0 with whichline. I E. connecter. The.. confV densate inseparator, IS-Separates. a..lower water condensate pro duct .and an.uppeiz oil..,con.A densate product. Both products thus lobtainedcontainalcohols and other oxygenatedorganic. compounds; those of lowermolecular. weist-htv tending to remain in thewater condensateprod.- uct,while those'of higher molecularweight. tend` to remain in. the oilcondensate product.. The water condensate productY is drawnoff .from-thebottom ofseparator I5 through-line I1. for. fur-- Thisl x ther use ortreatment outside the scope of the present process. The oil condensateproduct is drawn off at an intermediate point from separator I5 throughvalved-line I8. It should be noted that apparatus embodying more thanone separation stage may be employed, if desired; for example; primaryand*y secondaryv separation stages may'beintroduced, operatingsuccessively and respectively at temperatures of about 150 F. and aboutF.

The oil condensate product Withdrawn from separator" I5 comprising amixture of hydrocarbons, alcohols and other oxygenated organiccompounds, is next.transferred through valvedlin'efIto ai mixer I9. Inmixer I9 the aforementioned'mixturefiscontacted with carbondisuldeandanalkali, such as potassium hydroxide or sodium hydroxide,which are introduced into mlxer"I9 through lines 20 and 2I,respectively, in amounts sufficient to convert alcohols present in themixture to their corresponding xanthates; If

so desired'th'e reactants in mixer. I!!V maybev heatedT toY hastenthereaction. It should'. be'y noted-.that the alkali. thus introduced;into mixer IS'maybe eitherin anaqueous solutionzor in the' solid state,and may be introducedintotmixer. I9. either separately through line -2I,as showntin. the-drawing, or combined externally with carbon disulfideand the combined'Y mixture: introduced through line 20, if so desired.After--thedesired reactionhas-taken place inmixerv I9-, the resultingproductfofthe reaction; comprising a mixtureof hydrocarbons, xantha-tesand; other oxygenated organic compounds, is withdrawn through. line 22.This mixture is next transferred through line 22..tofa condenser 23 inorder to bring the'reaction mixtureto room' temperature.

The cooled mixture4 incondenser 23l is next transferred through line 24to a-low point in an extractiontovver 25. In tower 25I the mixture issubjectedto an intimate countercurrent Contact with. a. solvent having apreferential solvent power for. the. xanthates presentand is introducedat an upper. point through. line- 26. This .solvent comprises an aqueoussolution of a water-miscible compound. (ranging. from.. highly dilute toconcentratedlsolutions) such as` an alcohol, ketone or cyclic. ether(for.example; methanol, ethanol, acetone, methyl .ethyl ketone fordioxane) or may bewater. alone. The mixture introduced. through line.vHand; the solvent are. contactedv intower 25' under, conditionseffective. toabsorb in the solvent substantially allot. the.xanthatesccntainedinthe mixtureand thus effect separationY of thexanthates. fromother. oxygenated .organicl compounds andi. hydrocarbonspresent. As a result; of the foregoing. treatment` an upper oillayengcomprising hydrocarbcnsand alcohol-free oxygenatedorganiccompounds. and. a' loweraqueous layer comprisingxanthates of thealcoholspresent inthe feed in line.2!Iy are formed in towerA 25.. The upper.Yoilv layer. is.v withdrawn throughlinetZT for furthenuse. ortreatmentout-I side thescopeof thepresentprccess, whilethc lower aqueous'l'a'yercomprising xanthatesof the respective alcohols iswithdrawnthroughvalvedline. 28 as. an inteimediataproduct of .the-process of theinvention, or subjected to further treatment, as hereinafter. described;in order: to regenerate alcohols` from the:y thus'- formed xanthates.

In order to effect regeneration: of alcohols fromtheaforementionedaqueous' mixture of xanthates-.inf line 28, thisV mixture. ist nextvtransferred from line 28 through valved-line 29, with which line 28connects, to a mixer 30 where it is contacted with a mineral acid, suchas hydrochloric acid (shown in the drawing) or sulfuric acid, which isintroduced into mixer 30 through line 3|. As a result of the treatmentin mixer 30 there is obtained as the product of the reaction, a mixtureof alcohols, the alkali salt of the introduced mineral acid (potassiumchloride in the drawing) and reformed carbon disulfide. This mixture isnext transferred from mixer 30 through line 32 to a separator 33. Inseparator 33 the mixture introduced through line 32 is separated into anupper phase comprising relatively low-boiling alcohols present which arewithdrawn through line 34 together with the aforementioned reformedcarbon disulfide; and there is also formed a lower aqueous phasecomprising the alkali salt of the aforementioned mineral acid, which iswithdrawn as bottoms through line 35 for further use or treatmentoutside the scope of the present process. The mixture o-f alcohols andreformed carbon disulde in line 34 is next transferred to a distillationtower 36. In tower 36 the mixture introduced through line 34 is heatedunder proper operating conditions of temperature and pressure effectiveto distill overhead carbon disulfide present which is withdrawn throughline 31 and recycled through this `line for further use in mixer I9, vialine 20 with which line 31 connects. Bottoms from tower 36, comprising asubstantially water-free mixture of alcohols, are withdrawn through line38 as products of the process.

As hereinbefore indicated, the oil condensate product in line I8 may besubjected to a primary extraction treatment in order to effect theseparation of alcohols and other oxygenated organic compounds fromhydrocarbons present, prior to the aforementioned xanthate formation andsubsequent alcohol regeneration. For this purpose, the oil condensateproduct is transferred from line I8 through valved-line 39 to a lowpoint in an extraction tower 40. In tower the oil condensate productintroduced through line 39 is subjected to intimate countercurrentcontact with a solvent for the alcohols and other oxygenated organiccompounds contained therein. Such solvent may comprise a relativelylowboiling alcohol as methanol (as shown in the drawing), ethanol orpropanol, which is introduced into tower 40 at an upper point throughline 4I. The solvent treating agent and the oil condensate product arecontacted in tower 40 under conditions effective to absorb in thetreating agent substantially all of the alcohols and other oxygenatedcompounds present and thus effect separation of these compounds fromhydrocarbons presen As a result of the foregoing treatment, a loweralcohol layer and an upper hydrocarbon or oil layer are formed in tower40. Inasmuch as anhydrous light alcohols exhibit high solubilities .forhydrocarbons as well as for alcohols and `other oxygenated organiccompounds, dilution of suchalcohols will effect an improvement in theselectivity of extraction, so that absorption of hydrocarbons in thealcohol treating agent is substantially prevented. To obtain suchdilution, the alcohol solvent treating agent introduced into tower 40,through line 4I, may be employed as a dilute solution, or if so desired,the alcohol solvent may be introduced in an anhydrous state, while waterused for dilution may be introduced at an upper point above the alcoholinlet in tower 40. 'I'he use of additional water in the manner describedis eifective not only for the purpose of alcohol dilution, but itsintroduction at an upper point in tower 40 accomplishes the result ofwashing the upper hydrocarbon or oil layer free of the added alcoholtreating agent.

Following the above-mentioned treatment in tower 40, there is present anupper hydrocarbon or oil layer containing substantially al1 thehydrocarbons that were present in the oil condensate product enteringtower 40 through line 39, and a lower aqueous methanol layer containingalcohols and other extracted oxygenated organic compounds. The upperhydrocarbon or oil layer is withdrawn overhead as a raffinate from tower40 through line 42, for further use or treatment outside the scope ofthe present process, while the lower aqueous methanol layer is withdrawnas an extract through line 43. This extract is next transferred throughline 43 to a fractionation tower 44. Tower 44 functioning as a methanolstripper is operated under conditions eiiective to separate the aqueousmethanol layer introduced from tower 40 through line 43, into anoverhead alcohol fraction, comprising methanol, which is withdrawnthrough line 4I, and a bottom fraction comprising alcohols, otheroxygenated organic compounds and water. 'I'his bottom fraction iswithdrawn from tower 44 through line 45. The overhead alcohol fractionfrom tower 44 is cooled to liquefy the methanol component. Methanol thusliquefied is transferred through line 4I for repeated use as the solventtreating agent in tower 40 in the process hereinbefore described.Make-up methanol is introduced through line 46 via line 4I with whichline 46 connects. Bottoms from tower 44 comprising an aqueous mixture ofalcohols and other oxygenated organic compounds, as described above, arenext transferred through line 45 into mixer I 9, via line I8, forsubsequent xanthate formation and alcohol regeneration in the process ashereinbefore described.

The following examples will serve to illustrate, but are not intended inany way to unduly limit the process of the present invention.

Example I 1000 grams of an oil condensate product produced from thecatalytic hydrogenation of carbon monoxide was obtained. This producthad a composition, by weight, of: hydrocarbons, 15% alcohols (averagemolecular weight of 102) and 5% of other oxygenated organic compounds.Employing apparatus similar to that illustrated in the drawing of thepresent embodiment of the process of the invention, this mixture washeated under stirring with 80 grams of carbon disuliide and 88 grams ofa 50% aqueous solution of sodium hydroxide, for 15 minutes. Aftercooling to room temperature, the resulting reaction product wassubjected to counter-current extraction with a mixture comprising gramsmethanol and 200 grams water. To the resulting alcoholic extract wereadded grams of concentrated hydrochloric acid. After cooling andstratication, the resulting upper layer was decanted and methanol wasstripped by distillation. The residue, upon examination, was found toconsist of grams of an alcohol mixture, having an average molecularweight of approximately 102, and equal to that of the alcohols presentin the starting mixture.

Eample Il 1000 grams of a mixture of oxygenated organic compounds,obtained byextraction with aqueous methanol V(and.subsequent strippingofithe methanol solvent) of the aforementioned.olcondensateproduct inExample I, were analyzed and found to contain, by weight:75% alcohols(average molecular weight of .102) fand.15% of other oxygenated organiccompounds. Employing apparatus similar vto that illustratedin thedrawing ofthe present embodiment of .the process of the invention, thismixture was heated under stirring with 605 grams of carbon disulde and.445 grams of pulverized-potassium hydroxide for minutes. The resultingproduct was subjected Ato countercurrent Aextraction with 1000 grains ofa inixtureo acetone and water (:80 by volume) To the resulting extractwere added F750 v'grams `ci concentrated hydrochloric acid. Aftercooling 'and stratification, rthe `resulting upper layer was decantedand stripped of solvent. The residue, upon examination, was found toconsist of 720 gramscf an alcohol mixture vhaving an average molecularweight of approximately 104.

While a particular embodiment of the process ofthe present inventionhasbeen described, for purposes .of .illust-ration, it should be understoodthat various modifications yand adaptations thereof, Vwhich will beobvious to one skilled'in the art, .maybe made within the spirit. of-theinvention as setforth inthe appended claims.

Having'thus described my invention, I claim:

.1. A process crrecovering alcohols present'in an oil condensateproduct'obtained from the condensation-of the reaction effluent producedinthe hydrogenation of oxidesv rises: contacting said oil condensateproduct with carbon disulfide and `an alkali to convertalcoholscontained therein to theirl corresponding xanthates; contactingthe resulting mixture with an aqueous solution of at least one solventhaving a preferential solvent power for said xanthates selected from thegroup consisting or an alcohol, ketone and a cyclic ether to produce anextract phase and a raiinate phase; separating said phases; contacting'said extract phase with a mineral acidfto convert said xanthates vtotheir corresponding alcohols. and reform carbon disulde; separatingalcohols thus produced from said reformed carbon disulfide; andreturning separated reformed carbon disulfide for further contact withmore of said oil condensate product.

2. A process for recovering alcohols present in an oil condensateproduct obtained from the condensation of the reaction eiiluent producedin the hydrogenation oi oxides of carbon, which comprises: contactingsaid oil condensate product with a solvent for said alcohols to producean extract phase and a raffinate phase; separating said phases;contacting said extract phase with carbon disulfide and an alkali toconvert alcohols contained therein to their corresponding xanthates;contacting the resulting mixture with an aqueous solution of at leastone solvent having a' preferential solvent power for" said xanthatesselected from the group consisting of an alcohol, ketone and a cyclicether to vproduce arl-extract phase and a raffinate phase; separatingsaid phases; contacting said last-mentioned extract phase with a mineralacid to convert said xanthates to their corresponding alcohols andreform carbon disulfide; separating alcohols thus produced from saidyreformed carbon disulde; and returning separated reformed carbondisulde for further contact-withmore of said oil condensate product. I

ofcarbon, which coms :3. A process jfor recovering alcohols Ipresentinanfoil'condensate-product obtained from the condensation -of thevreaction effluent produced in the hydrogenation `of 'oxides of carbon,which comprises: contacting said'oil condensate product with carbondisulnde'and an alkali to convert alcohols contained therein to theircorresponding xanthates; contacting the resulting mixture with anaqueous solution of at least one solvent having a preferential solventpower for said xanthates selected. from the group consisting ofanalcohol, ketone and a cyclic ether to produce an extract phase and aranate phase; separating said. phases; contacting said extract phasewith a'mineral acid to convert said xanthates 'to their correspondingalcohols and reform carbon disulde; and separating'alcohols thusproducedfrom said'reormed carbon disulfide.

4. Thefprocess Vof;c1aim 3 wherein the. solvent for said xanthates is'an alcohol.

`5. The process of Yclaim 3 .whereinthe solvent forsaid xanthates ismethanol.

'6. The process of claim 3 wherein the solvent for said xanthates isethanol.

7. The process of Yclaim 3 wherein the solvent for said xanthates is aketone.

8. The processof .claim 3 wherein the solvent for said xanthates isacetone.

9. The process of vclaim 3 wherein the solvent for said xanthatesisfxnethyl ethyl ketone.

l0. The process of claim 3 wherein the solvent for-said xanthates isa-cyclic ether.

11. The process of claim 3 wherein the solvent for said xemtnates isfadioxane.

12. A process for recovering Yalcohols present in an oilcondensatcproduct obtained from the condensation of the` reactioneiliuent produced in the hydrogenation of oxides of carbon, whichcomprisesacontacting said oil condensate product with asolvent'ionsaidalcohols to produce an extract phase' and a raffinate phase; separatingsaid phases; contacting said extract phase with carbon disulfide-'and analkali to convert alcohols contained .therein to their correspondingxanthates;'-contactingthe resulting mixture with an aqueous solutionof;at least one solvent having a preferential -solvent'power for saidxanthates selected from'the'group consisting of an alcohol, ketone andacyclicether to produce an extract phase and a ,raffinate phase;separating said phases; contacting said last-mentioned extract phasewith a mineralacid to convert said xanthates to their correspondingalcohols and reform carbon disulfide; `and separating alcohols lusproduced'from said reformed carbon disul- 13. The process of claim 12wherein the solvent for saidalcohols vis an aqueous solution of awater-soluble alcohol.

14. The process of claiui12 wherein the solvent for 1said alcohols is anaqueous solution of methano 15. The process of clainr 12 wherein thesolvent for-said alcohols isan aqueous solution ofethanol'.

16. The process of Aclaim 12 wherein the solvent for said alcohols is anaqueous solution of propanel.

17. The process of claim 12 wherein the mineral acid is hydrochloricacid.

18. The processof claim 12 wherein the mineral acid is sulfuricgacid.

` -19. ii-process for recoveringalcohols present in an oil condensateproduct.' obtained from the condensation ofathe reaction effluentproduced in the hydrogenation of oxides of carbon, which comprises:contacting said oil condensate product with an aqueous solution ofmethanol to produce an extract phase and a raiiinate phase; separatingsaid phases; separating methonal from said extract phase; contacting theremaining portion of said extract phase with carbon disulfide andpotassium hydroxide to convert alcohols contained therein to theircorresponding xanthates; contacting the resulting mixture with anaqueous solution of dioxane to produce an extract phase comprising saidxanthates and a rainate phase comprising the remainder of said oilcondensate product, alcohol-free; separating said phases; contactingsaid last-mentioned extract phase with hydrochloric acid to convert saidXanthates to their corresponding alcohols and reform carbon disulde;separating alcohols thus produced from said reformed carbon disulfide;and returning separated reformed carbon disulde for further contact withmore of said oil condensate product.

20. A process for recovering alcohols present in an oil condensateproduct obtained from the condensation of the reaction product obtainedfrom the condensation of the reaction eiiluent produced in thehydrogenation of oxides of carbon, which comprises: contacting said oilcondensate product with an aqueous solution o1 methanol to produce anextract phase and a raiiinate phase; separating said phases; contactingsaid extract phase with carbon disulfide and 10 an alkali to convertalcohols contained therein to their corresponding xanthates; contactingthe resulting mixture with an aqueous solution of dioxane to produce anextract phase and a raiiinate phase; separating said phases; contactingsaid last-mentioned extract with hydrochloric acid to convert saidxanthates to their corresponding alcohols and reform carbon disulfide;and separating alcohols thus produced from said reformed carbon disulde.

' WILLIAM E. HANFORD.

References" Cited in the file of this patent STATES PATENTS Number NameDate 1,716,273 James June 4, 1929 1,838,547 Haslam Dec. 29, 19311,870,816 Lewis Aug. 9, 1932 2,037,718 Graves Apr. 21, 1936 2,101,649Groll Dec. 7, 1937 2,107,065 Van Peski Feb. 1, 1938 2,470,782 McGrath etal May 24, 1949 2,505,752 Burton May 2, 1950 FOREIGN PATENTS NumberCountry Date 15,777 Great Britain 1912 OTHER REFERENCES U. S. NavalTechnical Missions Report. Sentember 2, 1947, page 90.

1. A PROCESS FOR RECOVERING ALCOHOLS PRESENT IN AN OIL CONDENSATEPRODUCT OBTAINED FROM THE CONDENSATION OF THE REACTION EFFLUENT PRODUCEDIN THE HYDROGENATION OF OXIDES OF CARBON, WHICH COMPRISES: CONTACTINGSAID OIL CONDENSATE PRODUCT WITH CARBON DISULFIDE AND AN ALKALI TOCONVERT ALCOHOLS CONTAINED THEREIN TO THEIR CORRESPONDING XANTHATES;CONTACTING THE RESULTING MIXTURE WITH AN AQUEOUS SOLUTION OF AT LEASTONE SOLVENT HAVING A PREFERENTIAL SOLVENT POWER FOR SAID XANTHATESSELECTED FROM THE GROUP CONSISTING OF AN ALCOHOL, KETONE AND A CYCLICETHER TO PRODUCE AN EXTRACT PHASE AND A RAFFINATE PHASE; SEPARATING SAIDPHASES; CONTACTING SAID EXTRACT PHASE WITH A